diff --git a/composer.json b/composer.json
index e7c6ee8..875196c 100644
--- a/composer.json
+++ b/composer.json
@@ -25,7 +25,7 @@
         "psr-4": { "LIT\\MCP\\Tests\\": "tests/" }
     },
     "scripts": {
-        "test": "@php vendor/bin/phpunit",
+        "test": "@php -d memory_limit=512M vendor/bin/phpunit",
         "lint": "@php vendor/bin/phpcs"
     },
     "config": {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 6e7b6d4..e809d59 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -3,6 +3,10 @@
          xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
          bootstrap="tests/bootstrap.php"
          colors="true">
+    <php>
+        <!-- 1597+ tests with Mockery/Brain Monkey need ~180 MB; the CLI default is 128 MB. -->
+        <ini name="memory_limit" value="512M"/>
+    </php>
     <testsuites>
         <testsuite name="unit">
             <directory>tests/Unit</directory>